(19)
(11) EP 1 566 274 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
28.05.2008 Bulletin 2008/22

(43) Date of publication A2:
24.08.2005 Bulletin 2005/34

(21) Application number: 05076247.5

(22) Date of filing: 02.03.2001
(51) International Patent Classification (IPC): 
B41J 2/21(2006.01)
B41J 2/16(2006.01)
 B41J 2/14(2006.01)
(84) Designated Contracting States:
DE FR GB

(30) Priority: 10.03.2000 US 523238

(62) Application number of the earlier application in accordance with Art. 76 EPC:
01301914.6 / 1132214

(71) Applicant: Hewlett-Packard Company
Palo Alto, CA 94303 (US)

(72) Inventor:
  • Kawamura, Naoto
    Corvallis, OR 97333 (US)

(74) Representative: Jackson, Richard Eric et al
Carpmaels & Ransford 43-45 Bloomsbury Square
London WC1A 2RA
London WC1A 2RA (GB)

   


(54) Methods of fabricating fit firing chambers of different drop weights on a single printhead


(57) Inkjet printheads capable of printing smaller and larger drop-weight quantities of ink, and methods of manufacturing the inkjet printheads, are disclosed. The inkjet printhead (102) includes a substrate (204). One or more portions of the substrate may be etched such that the substrate might have different thicknesses. A thin-film layer (300) is connected to the substrate and contains independently addressable ink-energizing elements (224, 226, 228, 230), preferably resistors. An orifice layer (212) having a substantially planar exterior surface is applied directly to the thin-film layer. Consequently, the thickness of the orifice layer varies with the thickness of the substrate. At least one firing chamber (218, 220) is defined in each portion of the orifice layer with a different thickness and, preferably, different-sized resistors. Alternatively, the orifice layer has a substantially uniform thickness. In order to achieve the multiple drop-weight capability of the present invention, firing chambers of different volumes are provided. In this embodiment, firing chambers (402) that are to provide a larger drop-weight preferably have a more powerful ink-energizing element (406) and are laterally offset from the firing chamber nozzle aperture. Other firing chambers (400) that are to provide a small drop-weight preferably have a less powerful ink-energizing element (404) and are aligned with the firing chamber nozzle aperture. Thus, the present invention provides inkjet printheads capable of printing various drop-weight quantities of ink.







Search report